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Optical Conductivity of the Two-Dimensional Hubbard Model

Hiroki Nakano·Masatoshi Imada
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Abstract

Charge dynamics of the two-dimensional Hubbard model is investigated. Lancz$\ddot{\rm o}$s-diagonalization results for the optical conductivity and the Drude weight of this model are presented. Near the Mott transition, large incoherence below the upper-Hubbard band is obtained together with a remarkably suppressed Drude weight in two dimensions while the clearly coherent character is shown in one dimension. The two-dimensional results are consistent with previous results from quantum Monte Carlo calculations indicating that the Mott transition in this two-dimensional model belongs to the universality class characterized by the dynamical exponent of $z=4$.

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Hiroki Nakano, Masatoshi Imada. 1999-02-17. Optical Conductivity of the Two-Dimensional Hubbard Model. https://doi.org/10.1143/jpsj.68.1458

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